HFO-1234yf. Low GWP Refrigerant Update. Honeywell / DuPont Joint Collaboration

Transcription

1 HFO-1234yf Low GWP Refrigerant Update Honeywell / DuPont Joint Collaboration Barbara Minor DuPont Nacer Achaichia Honeywell European Automotive A/C Convention, Sept 22-23,

2 Background DuPont And Honeywell Have Identified HFO- 1234yf (CF 3 CF=CH 2 ) As The Preferred Low GWP Refrigerant Which Offers The Best Balance Of Properties And Performance Other Auto Industry Options Have Certain Limitations CO 2 : complexity, energy efficiency and requires mitigation 152a / secondary loop: performance, size and weight 2

3 3 HFO-1234yf The Leading Alternative Refrigerant to Replace R-134a Excellent environmental properties Very low GWP of 4, Zero ODP, Favorable LCCP Atmospheric chemistry determined and published Low toxicity, similar to R-134a Low acute and chronic toxicity Significant testing completed System performance very similar to R-134a Excellent COP and Capacity, no glide From both internal tests and OEM tests Thermally stable and compatible with R-134a components Potential for direct substitution of R-134a Mild flammability (manageable) Flammability properties significantly better than 152a; (MIE, burning velocity, etc) Potential for A2L ISO 817 classification versus A2 for 152a based on AIST data Potential to use in a direct expansion A/C system Global Solution Lowest total cost of transition than any alternative good performance in all climates, and car sizes

4 HFO-1234yf Properties Properties 1234yf 134a Boiling Point, T b -29 o C -26 o C Critical Point, T c 95 o C 102 o C P vap, MPa (25 o C) P vap, MPa (80 o C) Liquid Density, kg/m 3 (25 o C) Vapor Density, kg/m 3 (25 o C) yf CF 3 CF=CH 2 F 3 C F C CH Vapor Pressure 3 Pressure, MPa a 1234yf Temperature, o C 4

5 Excellent Environmental Properties ODP = Year GWP = 4 (GWP 134a = 1300) Measurements completed & published: Atmospheric Chemistry of CF 3 CF=CH 2 Chemical Physics Letters 439 (2007) pp Atmospheric lifetime = 11 days Atmospheric chemistry measured Atmospheric breakdown products are the same as for 134a No high GWP breakdown products (e.g. NO HFC-23 breakdown product) Results published in 2008 Good LCCP 5

6 DuPont and Honeywell feel comfortable with all toxicity test results conducted to date and will continue the commercialization of HFO-1234yf for use in MAC Based on toxicity testing conducted to date, including the second species developmental and the 2-Gen reproductive (1-gen interim results) studies, we believe HFO-1234yf will not be classified as a developmental or reproductive toxin, and it will likely be classified as ASHRAE Class A (low toxicity). There appear to be no health safety hazards or properties that would preclude the safe use of HFO-1234yf in MAC applications. 6

7 HFO-1234yf Toxicity Results Test HFO-1234yf 134a Acute Lethality No deaths 400,000 ppm No deaths 359,700 ppm Cardiac sensitization NOEL > 120,000 ppm NOEL 50,000 ppm LOEL 75,000 ppm 13 week inhalation NOAEL 50,000 ppm NOAEL 50,000 ppm Developmental (Rat) NOAEL 50,000 ppm NOAEL 50,000 ppm Genetic Toxicity Not Mutagenic Not Mutagenic 7 13 week genomic (carcinogenicity) 2-yr carcinogenicity Environmental Tox Developmental (Rabbit) 1-Gen segment of 2- Gen Reproductive Not active (50,000 ppm) Not required (see genomics) NOEL > 83 mg/l (Pass) NOAEL 4,000 PPM, LOAEL 5,500 PPM Interim NOAEL 5,000 ppm (6-hours exposures) Not tested Not carcinogenic NOEL > 100 mg/l (Pass) NOAEL 2,500 PPM LOAEL 10,000 NOAEL 50,000ppm (1-hour exposures) HFO-1234yf Has Low Toxicity

8 ATEL Calculation ATEL (Acute Toxicity Exposure Limit) is a value used by standards organizations (e.g. ASHRAE 34) to reduce the risks of acute toxicity hazards in normally occupied spaces. It is calculated from the acute toxicity data for a given refrigerant and provides an estimate of the maximum exposure limit for a short time period (e.g. 30 minutes) Refrigerant R-12 R-134a R-152a CO 2 HFO-1234yf ATEL (ppm) 18,000 50,000 50,000 40, ,000 HFO-1234yf Has a Favorable ATEL Value 8

9 System Bench Test Results Relative To 134a 120% 110% 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Capacity COP I45 L45 M45 H45 I50a I35a L35a M35a H35a I40c-3C I40c-10C I40a-3C I40a-10C I25a-3C I25a-10C L25a-3C L25a-10C M25a-3C M25a-10C H25a-3C H25a-10C I30-3C I30-10C I15-3C I15-10C L15-3C L15-10C M15-3C M15-10C H15-3C H15-10C charge 9 No changes were made to system including TXV; Industry standard test conditions Both Capacity and COP are generally within 5% of 134a performance. This was recently confirmed at two outside labs. Lower compression ratio, low discharge temperature (12 o C lower at peak conditions) Further improvements likely with minor system optimization, for example: Lower P suction line and / or TXV optimization to maintain a more optimum superheat. HFO-1234yf performance is comparable to 134a; further improvement possible with minor optimization HW/DuPont Data

10 10 100% 95% 90% 85% 80% 75% 70% 65% 60% 55% 50% Preliminary LCCP Analysis GM Model Using Bench Test Performance Results Relative to R-134a Shanghai Houston Boston Miami Frankfurt Athens Tokyo Kagoshima Sapporo Bangalore Bombay New Delhi Sydney Beijing Average 15% Better LCCP Values; Up to 27% in Europe JAMA and FIAT Obtained Similar Results Phoenix CO2 Eq. Emissions Relative to R-134a

11 1234yf: Excellent Plastics Compatibility ND8 PAG at 100 C for two weeks Refrigerant Plastics Rating 24 h Post Weight Chg. % Physical Change 1234yf Polyester " Nylon " Epoxy " Polyethylene Terephthalate " Polyimide Refrigerant Plastics Rating 24 h Post Weight Chg. % Physical Change R134a Polyester " Nylon " Epoxy " Polyethylene Terephthalate " Polyimide Rating 0 = best when weight gain < 1 and physical change = 0 1 = borderline when weight gain > 1 and < 10 and/or physical change upto 2 2 = incompatible when weight gain > 10 and/or physical change = 2 11

12 1234yf: Excellent Elastomers Compatibility ND8 PAG at 100 C for two weeks Refrigerant Elastomers Rating 24 h Post Linear Swell % 24 h Post Weight Gain % 24 h Post Delta Hardness Neoprene 1234yf 0 WRT " HNBR " NBR " EPDM " Silicone " Butyl rubber Refrigerant Elastomers Rating R134a 24 h Post Linear Swell % 24 h Post Weight Gain % 24 h Post Delta Hardness Neoprene WRT " HNBR " NBR " EPDM " Silicone " Butyl rubber Rating 0 = best when weight gain < 1 and physical change = 0 1 = borderline when weight gain > 1 and < 10 and/or physical change upto 2 2 = incompatible when weight gain > 10 and/or physical change = 2 12

13 MAFLOW Permeation HFO-1234yf vs R-134a Standard Veneer Hose MAFLOW ULEV Veneer Hose Permeation [g/m/d] on STD Veneer Hose ID13 Permeation [g/m/d] on ULEV Veneer Hose ID13 Artic 3 1,40 1,40 1,20 1,20 1,00 1,00 0,80 0,80 0,60 0,60 0,40 0,20 0,00 R134a C R134a 1234yf 0,40 0,20 0,00 Results HFO-1234yf shows lower permeability values toward Veneer hoses compared to R134a. Remarks With the same gas concentration (0.6g/cm³) the inner pressure with HFO-1234yf is lower (e.g: at 90 C was -20%) 13

14 Refrigerant Flammability Tests Is it flammable? If yes, Flame Limits will exist. LFL lower flammability limit UFL upper flammability limit What is the probability of an ignition source being present of sufficient energy to cause an ignition? Autoignition temperature Minimum ignition energy (MIE) What is the impact (damage potential) if an ignition occurs? Heat of combustion Burning velocity 14

15 HFO-1234yf Flame Limits LFL Values Ammonia 15 vol.% HFC vol.% HFO-1234yf flame limits measured using ASTM E T= 21 o C : 6.2 vol.% to 12.3 vol.% Low LFL value more flammable Wider UFL LFL more flammable HFO-1234yf 6.2 vol.% Methane HFC-152a Ethylene Oxide 4.6 vol.% 3.9 vol.% 3.0 vol.% ASTM E681 Apparatus Air In Refrigerant In ASTM E-681 in US 2004 version cited by ASHRAE (12 liter flask, spark ignition) Flame must reach the wall and exhibit > 90 degree angle 1985 version cited by SAE (5 liter flask, match ignition) Acetylene Propane 2.5 vol.% 2.1 vol.% Spark Ignition Stirrer A11 in EU 5 cm x 30 cm Vertical tube Spark ignition Flame travels up the tube Gasoline 1.6 vol.% More Flammable HFO-1234yf Is Less Flammable Than 152a 15

16 Burning Velocity Burning Velocity Measurements Measurements performed in 3 liter spherical apparatus Experimental result for HFO-1234yf: 1.5 cm s -1 ISO 817 Flammability Classification is 2L (lowest flammable class classification) 16

17 Minimum Ignition Energy 12-liter glass sphere used in ASTM E681 flammability limit tests was modified for MIE testing in order to eliminate potential wall quenching effects seen in standard 1 liter vessel Materials Tested: HFC-32 from 16-22% (v/v) in 1% increments at 30 and 100 mj nominal HFO-1234yf from % (v/v) in 0.5% increments up to 1000 mj nominal Ammonia at 22% (v/v) at 100 and 300 mj nominal Refrigerant No Ignition Occurred Ignition Occurred HFC /- 12 mj 100 +/- 30 mj Ammonia 100 +/- 30 mj 300 +/- 100 mj HFO-1234yf 5,000 +/- 350 mj 10,000 +/- 350 mj HFO-1234yf Is Very Difficult To Ignite With Electrical Spark 17

18 HFO-1234yf Mild Flammability Properties Flammability Properties Flammability Index LFL a UFL a MIE BV c (vol%) (vol%) (vol%) (mj) (cm/s) Propane R152a R b 6.7 Ammonia b 7.2 HFO-1234yf ,000-10,000 b 1.5 a Flame limits measured at 21 C, ASTM b Tests conducted in 12 litre flask to minimize wall quenching effects c Burning Velocity ISO 817 (HFO-1234yf BV measured by AIST, Japan) HFO-1234yf a Propane R = F = 1 RF = Cst LFL RF2 = R LFL UFL UFL 1 LFL Q M F RF {( ( UFL LFL) LFL) / LFL} Qst Su RF Cst = Stoichiometric composition in air, vol.% Q = Heat of Combustion per one mole Qst = Heat of Combustion per one mole of the Stoichiometric mixture, kj/mol Su = Burning speed in Meters/Second M = Molecular weight

19 Autoignition Temperature & Hot Surface Ignition The autoignition temperature of HFO-1234yf was determined at Chilworth Technology in UK. Uniformly heated 500 ml glass flask, observed in dark for 10 mins. Autoignition temperature for HFO- 1234yf determined to be 405 o C. Note that the air refrigerant mixture must be at this temperature for ignition to occur. Experiments were conducted to evaluate the ignition potential of hot surfaces (up to 800 o C) to cause ignition. 6 mm steel plate heated from behind with propane-oxygen torch No ignition seen HFO-1234yf vapor sprayed onto the plate Infrared Thermometer measured temperature. Three dots seen are to aim the thermometer Occasional red circles are diffraction rings from the camera lens reflecting the red plate through the refractive index gradient (caused by hot air / cold refrigerant). 19

20 Summary of Hot Plate Tests Hot Manifold 550 C Faint Red 800 C Cherry Red >900 C Orange Spray No oil No ignition No ignition No ignition HFO-1234yf Premixed with air no oil Not tested No ignition No ignition with PAG oil No ignition No ignition Ignition Spray no oil No ignition No ignition No ignition R-134a Premixed with air no oil Not tested No ignition No ignition 20 with PAG oil No ignition No ignition Ignition HFO-1234yf shows same flammability behavior as R-134a - Ignition due to presence of oil

21 HFO-1234yf Ignitability to Spark from 12-V Battery Short Circuit The purpose of these tests is to determine whether a spark caused by a short circuit from a 12-V battery located under the seat is capable of igniting an optimum concentration of HFO-234yf in air Follow procedures from ASTM E681 in a sealed 12-l spherical flask; add moisture equivalent to 50% RH at 23 o C Create a short-circuit in the mixture by discharging a high-capacity 12-V automotive battery (1020 cranking amps) across 9.5 mm diameter copper electrodes located in the sphere No ignitions observed at 8.13, 8.5, and 9.0% HFO-1234yf at either 20 o, 60 o or 80 C (10 trials per concentration) For comparison the ignitability of ammonia, a refrigerant of relatively low flammability, was tested at a 20% v/v concentration at 20 C and 60 o C; positive test was obtained on the first trial 21

22 Battery Ignition Apparatus 12-l Sphere Containing 1234yf/Air 9.5 mm Stationary Copper Electrode Moveable 9.5 mm Copper Electrode Automotive Cables High Current 12-V Switch 12-V/1020 CA Battery 22

23 Risk Assessments For most fires to happen, fuel and air at the right concentration, and an ignition source, with a sufficient energy level must co-exist at the same place and in the same time. Several risk assessments have been completed or are in progress in US (SAE CRP-1234), Japan (JAMA) and Europe utilizing inputs of modeling and leak experiments Release Experiments Cabin and underhood Normal operation and crash condition Service (Professional and DIY) CFD modeling to visualize concentration distribution for various scenarios. R152a HFO- 1234yf 23

24 SAE CRP-1234 Risk Assessment Results Risk Typical Associated Everyday with Leaks of HFO-1234yf Risks Table 26. Risks of Injury or Fatality from Various Events Compared to Risks Risk per year Citation Risk of stroke Fatal accident in the home Fatal accident while climbing mountains (if mountaineer) Risk of being injured as a pedestrian Fatal injury at work (all occupations) Injury from lightning strike Risk of being fatally injured in an elevator ride 2.7 x x x x x x x10-7 Rhys Williams, 2001 Wilson and Crouch, 1987 Wilson and Crouch, 1987 NSC, 2004 NSC, 2004 NWS, undated** McCann and Zalesky, Risk of exposure to HFO-1234yf above health based limits resulting from a collision Risk of being injured by an HFO-1234yf ignition resulting from a collision 1 x x *Risk cited is 1 in 10,000 over the next century # Injury sufficiently serious to require hospital visit. Based on number of injuries per year divided by total U.S. adult population. Total number of injuries requiring hospital visit per year divided by the total U.S. population. ** Total number of documented injuries from lightning strikes per year, divided by total U.S. population. & FTA risk multiplied by the number of estimated drivers in the U.S.. CRP1234 Analysis CRP1234 Analysis

25 Handling HFO-1234yf Will Be Handled Similar to R-134a Distribution of HFO-1234yf from manufacturer to auto OEM plants and after sales service markets will be similar to R-134a Minor changes to plant charging equipment and procedures HFO-1234yf can be recovered, recycled and reused on site at service shops HFO-1234yf leaks can be detected with same equipment as R- 134a Unique fittings will be used ensure no cross contamination with R-134a 25

26 26 Service Readiness

27 27 Recyclability

28 28 Recyclability

29 Path Forward Plant Process Design & Planning SNAP/ASHRAE applications REACH application In progress Filed In progress Obtain Industry convergence/oem commitments Sep-Oct 2008 Industry adoption of HFO-1234yf Firm volumes projections to finalize facility plans (June 2008) Plant Construction end & plant start-up Nov

30 30 HFO-1234yf The Leading Alternative Refrigerant to Replace R-134a Excellent environmental properties Very low GWP of 4, Zero ODP, Favorable LCCP Atmospheric chemistry determined and published Low toxicity, similar to R-134a Low acute and chronic toxicity Significant testing completed System performance very similar to R-134a Excellent COP and Capacity, no glide From both internal tests and OEM tests Thermally stable and compatible with R-134a components Potential for direct substitution of R-134a Mild flammability (manageable) Flammability properties significantly better than 152a; (MIE, burning velocity, etc) Potential for A2L ISO 817 classification versus A2 for 152a based on AIST data Potential to use in a direct expansion A/C system Global Solution Lowest total cost of transition than any alternative good performance in all climates, and car sizes

31 For further information on HFO-1234yf please visit: and Thank you! DISCLAIMER Although all statements and information contained herein are believed to be accurate and reliable, they are presented without guarantee or warranty of any kind, expressed or implied. Information provided herein does not relieve the user from the responsibility of carrying out its own tests and experiments, and the user assumes all risks and liability for use of the information and results obtained. Statements or suggestions concerning the use of materials and processes are made without representation or warranty that any such use is free of patent infringement and are not recommendations to infringe on any patents. The user should not assume that all toxicity data and safety measures are indicated herein or that other measures may not be required. 31